according to the Western States Ride Calendar, the only "orgainzed" century is Cool breeze, which sells out. It's usually too hot for a lot of folks to do that distance.
I did it last year and it wasn't remotely hot (maybe a fluke?)... overcast in the morning w/ocean breezes in the afternoon...
It hasn't sold out yet so sign up!!! This is a favorite of many people!!! Fredwina, you should be there too!